the providers

 Signature Internal Medicine

Concierge Internal Medicine in Frisco, TX

Dr. Ahmed and Dr. Diehl

Open Enrollment Starting August 2022

Open Enrollment Starting August 2022
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About Signature Internal Medicine

Signature Internal Medicine is a superior concierge internal medicine practice in Frisco, Texas, led by Humera Ahmed, MD, and Dina Diehl, DO. The skilled providers offer comprehensive primary care services for men and women 18 and older.

Signature Internal Medicine offers 24/7 access to physicians any time patients need them. Providers spend as much time as patients desire to ensure exceptional care, so appointments never feel rushed.


  • 24/7 access to a physician
  • More time spent with providers
  • Little or no office wait times
  • Exceptional primary care
  • Superior results
  • Comfortable, friendly environment
  • Improved disease management
  • Early disease detection
  • Cutting-edge diagnostics and treatments
  • Same-day or next-day appointment availability 
  • Personalized attention
  • Specialist referrals 
  • Coordination of follow-up care 
  • White glove service 

Annual membership: individual $3000/year, couples $5000/year. This fee is not covered by insurance. Our annual membership covers these practice benefits. We accept most insurances for medical visits, labs, and diagnostic testing if applicable. You may request a complimentary meeting with one of our providers to see if they are right for you.

Well-trained, experienced physicians at Signature Internal Medicine specialize in preventive health care, annual physicals, comprehensive internal medicine services, and more.

The practice provides exceptional concierge medicine, which is a newer approach to healthcare in which your primary care physician limits the size of the practice. This allows them to spend more time with patients and deliver the personalized attention they deserve.

Along with 24/7 access to your provider, concierge medicine provides same-day or next-day appointments with little to no office wait times. Your Signature Internal Medicine provider focuses on patients’ unique needs, tailoring treatment plans just for them.

The highly-trained providers care for patients with diabetes, chronic obstructive pulmonary disease (COPD), high cholesterol, hypertension, osteoporosis, gastrointestinal reflux disease (GERD), and mental health conditions. 

Signature Internal Medicine offers medical weight loss, chronic disease, and acute illness management, prescription medicines, cancer screening, smoking cessation, on-site diagnostic testing, and much more. The internal medicine providers work and communicate closely with specialists, referring patients to them when necessary.

The Signature Internal Medicine specialists warmly welcome their patients to the practice and look forward to caring for them. 

Call the office or use the online booking tool today to schedule an appointment at Signature Internal Medicine.

Meet Our Providers

Dr. Diehl and Dr. Ahmed currently have privileges at Texas Health Hospital Plano & Texas Health Hospital Frisco
Dr. Diehl

- American College of Physicians
- Member of Institute of Functional Medicine
- National Committee for Quality Assurance Excellence in Diabetes Care 2017
- Board member at Texas Health Presbyterian, 2010 
- Certificate of Recognition for Delivery of Quality Cardiovascular and Stroke Care 2017-2020

- America's Most Honored Professionals 2019 - Top 5%
- America's Most Honored Professionals 2018 - Top 1%
- America's Most Honored Professionals 2017 - Top 5%
- Compassionate Doctor 2015
- Compassionate Doctor 2016
- On-Time Physician Award - 2016
- On-Time Physician Award - 2015
- Patients' Choice 2016
- Patients' Choice 2018

Dr. Ahmed

- D-Magazine Best Internist in 2018 and 2019 
- National Committee for Quality Assurance Excellence in Diabetes Care, 2017
- Recognized for Delivery of Quality Cardiovascular and Stroke Care, 2017-2020
- Board member at Texas Health Presbyterian, 2010
- Member of the American College of Physicians
- Member of Obesity Association
- Top doctors of America selected in 2022
- America's Most Honored Doctors - Top 5% 2022
- America's Most Honored Doctors - Top 5% 2021
- America's Most Honored Doctors 2020 - Top 5%
- Compassionate Doctor 2020
- On-Time Physician Award - 2020
- Patients' Choice 2020
- Patients' Choice 2019

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Patient Reviews

Coming Soon!
Wonderful personal care! It’s great to work with a doctor that takes the time to help you with each and every concern.

Tammie W. | Sep 12, 2022

Elaine smith | Sep 04, 2022
Dr. Ahmed has been my dr for 4 years and I don’t regret it one bit. She is very thorough and does not sugar coat anything which I LOVE. She is sweet and kind, she loves all her patients. Also she is always very informed about my medical history because she documents very well in her computer. She always does her absolute best to get your medical condition under control or on the right meds she does not give up on her patients. I’ve had many PCP’s in the past and I completely trust Dr. Ahmed with my own medical care and my family members

Jessica Carias | Sep 01, 2022

Riffat Munawar | Aug 26, 2022
Very friendly informative knowledgeable and caring!!

Judy D. | Aug 24, 2022
My experience with Dr. Diehl has been excellent. She is very professional, knowledgeable, and caring. Having a personal and confidential relationship with my doctor is very important and Dr. Diehl provides that. The staff is also very friendly and helpful ensuring that I fully understand my healthcare. I would absolutely recommend them to friends and family.

Christi Mitchell | Aug 20, 2022
I have known Dr. Diehl and Dr. Ahmed both for over 10 years. Extremely talented and professional physicians that I highly recommend.

Jennifer Sheehan | Aug 19, 2022
I have been a patient of Dr. Ahmed's for many years, she was referred to me by another doctor. Dr. Ahmed is extremely knowledgeable, caring, and listens to all concerns. I have referred many friends to her.

Kristen Murphy | Aug 19, 2022
Dr. Diehl is the most thorough Doctor I have ever been too! She really cares about her patients and has their best interests at heart! It is so convenient and easy to see her if you get sick etc. I Highly Recommend her and the concierge service she provides!

Brad Hansing | Aug 19, 2022
Been with Dr. Ahmed for many years, she's a first class Internal MD who actually looks for the problem and a treatment.

Scott Copeland | Aug 19, 2022
Dr Ahmed provides comprehensive and compassionate care in an efficient and friendly manner

Pat L. | Aug 19, 2022
Dr. Diehl and Dr.Ahmed are both extremely talented and professional physicians. They take their time to truly understand any questions, comments or concerns at every visit. I have never met any other physician with the bed side manner and professionalism these two have. BRAVO!

Lindsay Sewell | Aug 19, 2022


We accept most insurance providers. If you have specific questions regarding your coverage, please contact us for additional information.

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